package cn.Collection;

import java.util.ArrayList;
import java.util.Collection;

public class CollectionDemo {
    public static void main(String[] args) {
        Collection<String> c = new ArrayList<>();
        c.add("a");
        c.add("b");
        c.add("a");
        //移除指定的首个出现的元素
        c.remove("a");

        c.clear();

        System.out.println(c.contains("f"));
        System.out.println(c);
    }
}
